the feeling of complete happiness/understanding one gets from any number of things. Such things include listening to a mindblowing guitar riff, or seeing a person you hate get screwed, among countless other things.

After listening to Hysteria, I can hardly think due to the intense mindgasm it brought me to.

After hearing Kristin got fired, I laughed for two straight minutes and smiled for the rest of the week. It was purely mindgasmic.